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The following is a discussion of some astronomical objects to view during the week of Sept. 21 to Sept 27, 2008.

International Space Station

Sun. Sept. 21 at 8:22 ISS appears in the west and disappears into the earth shadow in the NNE at 8:27. Reaches magnitude -0.5
Mon. Sept 22 ISS appears in the SW at 7:13 pm and disappears in the NE at 7:19 pm. Reaches magnitude -2.3
again in the WNW at 8:50 pm and disappears in the NE at 8:52 pm in the north reaches magnitude 0.6
Tues Sept 23 ISS appears in the west at 7:40 pm and disappears in the NNE at 7:46 pm MDT

See www.heavens-above.com for times when the International Space Station is visible over your location.

Sun

On Sun. Sept. 21 sunrise is at 6:50 am and sunset is at 7:01 pm mdt
On Sat. Sept. 27 sunrise is at 6:55 am and sunset is at 6:51 pm mdt

There is currently a new region 11002 at solar coordinates N25 and W27 (Monday evening). For current locations of solar regions see www.raben.com/maps The MacIntosh classification of the region is Dso, it has a Beta magnetic configuration and 8 sunspots are visible. It is new cycle as as the magnetic polarity is opposite the previous cycle. For more information about the sun and space weather see www.swpc.noaa.gov

Moon

On Sunday, the moon is at lunation 22.4.
At moonrise on Saturday morning the moon is at lunation 28.7.

Planets

The planets Mars and Venus are visible low in the west after sunset. On Saturday, Mars sets at 7:30 pm. It is 1.7 magnitude in brightness and its disk is 3.8 arc sec across. You'll need binoculars to see it in the bright twilight sky after sunset. Venus sets at 8:01 pm. It is magntiude -3.8 in brightness and thye planets disk is 12 arc sec across. It should be easy to find naked eye.

Jupiter is straight south at 7:20 pm and sets at midnight. The GRS crosses the meridian at the following times this week:
Sun. Sept. 21 at 10:52 pm
Wed. Sept. 24 at 8:22 pm
Fri. Sept. 26 at 10:01 pm

Neptune is in constellation Capricornus it is magnitude +7.9 in brightness, disk is 2.3 arc sec across.

Uranus is in constellation Aquarius. It is magnitude +5.7 in brightness and the disk is 3.7 arc sec across as seen from telescopes on earth.

Saturn rises at 5:05 am in constellation Leo an hour and 50 minutes before sunrise. It is currently magnitude 1.1 in brightness and the planet's disk is 16.2 arc sec across.

Comets

17P Holmes is in constellation Cancer Large faint diffuse object 1-2 degrees across and about magnitude 6.1, use binoculars.

6P d'Arrest is in constellation Grus (below Aquarius). Look straight south around 10:30 pm. magnitude +8.5

19P Borrelly is in constellation Leo Minor magnitude 11.3

C/2006 OF2 Broughton is in Camelpardalis 11.1

C/2008 J1 Boattini is in constellation Camelpardalis as well and is magnitude 11.5

C/2006 W3 Christensen is in constellation Cassiopea 11.7

C/2007 W1 Boattini is in constellation Pisces magnitude 10.6

C/2007 N3 Lulin is in constellation Ophiuchus and is magnitude 10.7

Dark Sky Objects

The nights are getting longer and a bit chillier. There always some great objects to view especially on a dark sky weekend. Get away from city lights and view Messier 31 in constellation Andromeda. To locate it, find the four bright stars outlining the the great square of Pegasus. Start at the northeast corner of the square (Alpheratz) and note the line of 3 stars pointing toward Perseus. Locate the second star (Mirach). Move nearly perpendicular to the line and locate the 3.9 magnitude star Mu Andromeda. Continue along the line the same distance and you'll see Messier 31. The view through binoculars or a wide field telescope in dark skies is spectacular. The galaxy is almost 3 degrees across so it nearly fills half the field of the view in 10x50 binocular. Messier 31 is our closest large neighboring galaxy. It is 2.5 million light years distant and contains about one trillion stars.

Summary

This week you can view the planets Mars, Venus, Jupiter, and Saturn; locate some faint comets; and see our largest neighboring galaxy in space, Messier 31, the great andromeda galaxy.